Spec cleanup/reorganization

Back-ported from my still-in-progress major cleanup.

See docs for usage

Changes:
* Move spec/monkeypatch to spec/support
* Remove unused support/shared_examples
* Move support/api to support/api_helpers to match module name
* Move support/login to support/login_helpers to match module name
* Move API specs to requests/api (convention over configuration)
* Remove unused support/js_patch
* Simplify login_as helper
* Move DatabaseCleaner stuff to its own support file
* Remove unnecessary configuration and requires from spec_helper

fix merge request form

Hide the gravatar tip in the profile menu if gravatar is disabled.

fix git push body bigger than 112k problem

Allow disabling Gravatars in gitlab.yml settings

2. SSH Keys Help page

Misspelled Draper

fix inline forms

Gemfile cleanup

:)

Improve GFM code documentation

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Don't run SimpleCov on Travis